When you see them for the first time, you’re amazed by their size. Wading in the shallows, the whooping cranes stand almost 5 feet, the tallest birds in America. Although they may look gangly walking on stilt-like legs, they can also suddenly sail skyward on sleek, black-tipped wings. And this time of year the rare birds do more flying than walking, as they make an annual 2,500-mile migration trip from Canada’s Wood Buffalo National Park to the Aransas National Wildlife Refuge in Texas, where they’ll winter until April when they return to Canada for the summer.

Although whooping cranes in this flock today number around 300 (out of about 500 in existence), that’s actually a remarkable improvement. Decades of conservation efforts have helped bring the giant birds back from near extinction after an all-time low of 15 in 1941. The credit for much of that success goes to the U.S. Fish & Wildlife Service, which has been studying the birds for more than 70 years. Two years ago, Service wildlife specialists attached GPS monitors to 24 Texas-traveling birds (19 are still active today) to learn what effect the construction of wind energy towers and power transmission lines may have on their migration. “There are thousands of wind turbines located in the migration corridor, and power lines can also be a danger,” explains Tom Stehn, the former whooping crane coodinator for the Service. Once in Texas, the cranes spread out over a 35-mile-long stretch along the Gulf Coast, with about half of them nesting in the Aransas National Wildlife Refuge and the neighboring Matagorda Island Unit. The rest settle on private lands where they spend their days munching on acorns, wolf berries, and especially blue crabs.“An adult crane can eat as many as 80 blue crabs a day,” Tom says. “As you can see, they’re pretty big birds.”

Whooping Crane CruisesTo see whooping cranes up close, take a tour:

Aransas Bay Birding Charters runs six-hour cruises for small groups from Rockport ($350 for up to six people). texasbirdingphotos.net